Cam operated ignition point assembly

ABSTRACT

An improved set of ignition points for use in automobile engines and the like in which the points are opened and closed by a plunger wherein the moving point is maintained parallel to the fixed point by a pair of guide pins. The points are mounted on a base member which contains a plurality of holes to permit the points to be used as a direct replacement.

I United States Patent [1 1 1111 3,781,494 Tremarco Dec. 25, 1973 CAM OPERATED IGNITION POINT 2,810,796 10/1957 Russell 200/30 A ASSEMBLY 2,814,682 11/1957 Russell 1. 200/30 A 3,055,992 9/1962 Sargis ZOO/30 A Inventor: Paul Tremarco, Hewitt, J 3,182,142 5/1965 Hartman, Jr 200/30 A Assignee: Edson Enterprises, Inc, Hewitt NJ 3,347,999 10/1967 Penrose 200/30 A Filed! J 1973 Primary Examiner-J. R. Scott 2 p No: 322 113 Attorney-John C. Altmiller 52 us. Cl. 200/30 A [57] ABSTRACT [5 1] Int. Cl. 01]. 19/62 An improved set of ignition points for use In automo- [58] Field of Search 200/19 R, 19 A, 26, bile engines and the like in which the points are 200/27 A, 30 R, 30 A, 30 AA, 31 R, 31 A, opened and closed by a plunger wherein the moving 31 DP, 166 BE, 166 BF point is maintained parallel to the fixed point by a pair of guide pins. The points are mounted on a base mem- [56] Refer Cit d her which contains a plurality of holes to permit the UNITED STATES PATENTS points to be used as a direct replacement. 2,664,474 12/1953 Chermendy 200/30 A 11 Claims, 3 Drawing Figures BACKGROUND OF THE INVENTION 1. Field of the Invention DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT The construction and manner of operation of the pre- This invention relates to automotive ignition systems ferred embodiment of the invention is illustrated by the in general and more particularly to improved ignition points for use in such systems.

2. Description of the Prior Art In most prior art ignition points commonly used in automobile distributors, there is provided a fixed point and a movable point on an arm operated by the distributor cam. The arm on which the movable point is mounted is free to rotate about a fixed pin and is held against a fixed point by spring tension. Lobes on the cam push against a cam follower on the arm to move the arm and thus open the points to a predetermined gap. This type of point operation is shown in US. Pats. Nos. 2,740,853 and 3,575,579. Because the arm on which the movable point is mounted is hinged about a pin, the point surfaces are not always parallel when the points are opening and closing. This causes uneven wearing of the points, pitting and, at high speeds, may also cause skipping of the points resulting in misfiring.

When the engine is operating improperly because of pitted or worn points, improper combustion occurs resulting in the emission of pollutants. With the increased awareness of the problems of air pollution and the strict standards being placed on automobile emissions by Federal and State governments, it is increasingly important that efficient engine operation be maintained. With present day ignition systems, frequent replacement of points is required to maintain the high standards imposed. Some older systems may not even be able to meet the standards with new points. Thus there is a need for a system which will enable efficient combustion and which may be used as a direct replacement for the points presently installed in older engines.

SUMMARY OF THE INVENTION The point arrangement of the present invention eliminates the problems of the hinged arm of the prior art by causing the movable point to always move parallel to the fixed point. The fixed point is mounted to one of two vertical members on a bracket fixed to the distributor. A plunger having mounted on it a holder holding the movable point is free to move in slots in the vertical members of the bracket and is positioned to contact the distributor cam. Guide pins passing through the two vertical members and the holder maintain the points in a parallel relationship as the plunger moves in and out. Springs are placed over each of the guide pins to keep the points in contact when no force is being applied to the plunger by the cam.

The points are also designed so that they may be used as a direct replacement for points presently installed in all automobiles made by the major automobile manufacturers. Thus the present points will aid the owner of an older car in bringing the engine up to the new emission standards.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is an exploded view of the preferred embodiment of the ignition points of the present invention;

FIG. 2 is a plan view of the embodiment of FIG. 1; and

FIG. 3 is a side view of the plunger of FIGS. 1 and 2.

exploded view of FIG. 1 and the plan view of FIG. 2. A base bracket 11 is provided which may be mounted to a distributor base plate means 13 by screws 15 through selected ones of holes 17. A plurality of holes 17 are provided to permit mounting the point assembly to any of the distributors used by the major American automobile manufacturers. The bracket 11 has a first vertical portion 19 and a second vertical portion 21 parallel thereto. Each of the vertical portions 19 and 21 contains a slot 23 and two holes 25 and 27. Portion 19 contains a further hole 29 into which is press fitted a point 31. Bracket 1 1 may be formed of sheet metal and point 31 should preferably be made of tungsten. A plunger 33 of a size which will permit sliding within slots 23 is inserted through the slots. Plunger 33 has a rounded end 35 which rides on the cam 37. An insert 38 of a hard material such as steel or hard brass may be inserted in a slot in the plunger 33 to avoid wear of the plunger material which will preferably be of fiber or plastic composition. A rectangular recess 39 is provided on the top of the plunger 33 to accept a point holder bracket 43. A threaded hole 41 is provided in plunger 33 to permit fastening the holder 43 thereto through the elongated hole 45 with a screw 47. Holder 43 contains holes 49 and 51 which are aligned with holes 25 and 27 on bracket 11. Holes 49 and 51 are of a size slightly larger than holes 25 and 27 to permit insertion of bushings 53 therein. Holder 43 contains another hole 55 into which the other point 57 is press fitted.

Guide pins 59 and 61 are inserted respectively through holes 25 and 27 and 51. Pins 59 and 61 are held fixed in the holes 25 and 27 by press fitting or the like. Bushings 53 should preferably be of a plastic material to permit good sliding friction and to insulate holder 43 from bracket 11. Similarly, plunger 33 should be a non-conductive fiber or plastic material. If it is formed of conductive material, insulation must be provided between plunger 33 and holder 43. Holder 43 is provided with a terminal 67 to which a condenser 69 may be connected in conventional fashion.

The assembly will be mounted to the distributor as shown in FIG. 2. With one of the lobes 71 of cam 37 contacting the plunger end 35, the screw 47 may be loosened and the position of holder 43 adjusted to the specified gap after which screw 47 may be tightened. As the cam rotates the points will be opened each time a lobe contacts the end 35. Between lobes, when on the flat of the cam, springs 63 will hold the points closed. The resulting motion between the points will cause them to always be parallel thus eliminating uneven wearing of the points and substantially reducing pitting and mis-firing at high speeds.

Thus an improved ignition point apparatus in which the point surfaces are always maintained parallel has been shown. Although a specific embodiment has been described, it will be obvious to those skilled in the art that various modifications may be made without departing from the spirit of the invention which is intended to be limited solely by the appended claims.

Having thus described a typical embodiment of my invention, that which I claim as new and desire to secure by letters patent of the United States is:

1. Distributor point apparatus comprising:

a. a base member having a horizontal portion containing mounting holes and first and second parallel spaced vertical sections each of said sections having a slot therein;

b. a plunger inserted through said slots and having portions extending out from each of said first and second vertical sections for sliding motion therein;

c. a point holder having a horizontal portion and a vertical portion mounted tosaid plunger for motion therewith between said first and second vertical sections, said vertical portion containing two guide holes;

d. first and second guide pins inserted through said guide holes and making sliding contact therewith, said first and second pins each being affixed to said first and second vertical sections;

e. a movable contact point secured to the side of said holder vertical portion closest to said first vertical section of said base;

f. a fixed contact point affixed to the side of said first vertical section closest said point holder in alignment with said movable contact;

g. means to insulate said point holder from said base;

and

h. first and second springs placed over said first and second guide pins between said holder vertical portion of said second vertical section urging said movable point against said fixed point whereby said base member may be mounted to a distributor base plate means with the portion of said plunger extending from said first vertical section arranged to contact said distributor cam thereby permitting said cam to separate the points with said guide pins maintaining the point surfaces parallel.

2. The invention according to claim 1 and further ineluding a terminal on said holder for connecting a condensor wire.

3. The invention according to claim 1 wherein said base member contains a plurality of sets of holes.

4. The invention according to claim 3 wherein holes are provided for mounting to various distributors base plate means 5. The invention according to claim 1 wherein the end of said plunger extending from said first vertical section has a rounded end portion.

6. The invention according to claim 5 wherein said plunger is made of a non-conductive material and further including plastic bushings inserted in the holes in said holder insulating said pins from said holder.

7. The invention according to claim 6 wherein said first and second vertical sections of said base each contain two holes aligned with the holes in said holder and each of first and second guides are inserted through a hole in said first vertical section, a hole in said holder vertical portion and a hole in said second vertical section, said pins having one end enlarged to prevent passing through said holes and having their other end affixed to said second vertical section.

8. The invention according to claim 6 wherein said pins lie in the same horizontal plane.

9. The invention according to claim 6 wherein said plunger contains a slot in saidrounded end into which a hard material is inserted.

10. The invention according to claim 6 wherein said holder is affixed to said plunger by a bolt inserted through a slotted hole in said horizontal portion of said holder screwed into a threaded hole in said plunger whereby the point gap may be adjusted by sliding said holder within the limits of said slot.

11. The invention according to claim 10 wherein said plunger contains a recess into which said horizontal portion of said holder is inserted. 

1. Distributor point apparatus comprising: a. a base member having a horizontal portion containing mounting holes and first and second parallel spaced vertical sections each of said sections having a slot therein; b. a plunger inserted through said slots and having portions extending out from each of said first and second vertical sections for slIding motion therein; c. a point holder having a horizontal portion and a vertical portion mounted to said plunger for motion therewith between said first and second vertical sections, said vertical portion containing two guide holes; d. first and second guide pins inserted through said guide holes and making sliding contact therewith, said first and second pins each being affixed to said first and second vertical sections; e. a movable contact point secured to the side of said holder vertical portion closest to said first vertical section of said base; f. a fixed contact point affixed to the side of said first vertical section closest said point holder in alignment with said movable contact; g. means to insulate said point holder from said base; and h. first and second springs placed over said first and second guide pins between said holder vertical portion of said second vertical section urging said movable point against said fixed point whereby said base member may be mounted to a distributor base plate means with the portion of said plunger extending from said first vertical section arranged to contact said distributor cam thereby permitting said cam to separate the points with said guide pins maintaining the point surfaces parallel.
 2. The invention according to claim 1 and further including a terminal on said holder for connecting a condensor wire.
 3. The invention according to claim 1 wherein said base member contains a plurality of sets of holes.
 4. The invention according to claim 3 wherein holes are provided for mounting to various distributors base plate means
 5. The invention according to claim 1 wherein the end of said plunger extending from said first vertical section has a rounded end portion.
 6. The invention according to claim 5 wherein said plunger is made of a non-conductive material and further including plastic bushings inserted in the holes in said holder insulating said pins from said holder.
 7. The invention according to claim 6 wherein said first and second vertical sections of said base each contain two holes aligned with the holes in said holder and each of first and second guides are inserted through a hole in said first vertical section, a hole in said holder vertical portion and a hole in said second vertical section, said pins having one end enlarged to prevent passing through said holes and having their other end affixed to said second vertical section.
 8. The invention according to claim 6 wherein said pins lie in the same horizontal plane.
 9. The invention according to claim 6 wherein said plunger contains a slot in said rounded end into which a hard material is inserted.
 10. The invention according to claim 6 wherein said holder is affixed to said plunger by a bolt inserted through a slotted hole in said horizontal portion of said holder screwed into a threaded hole in said plunger whereby the point gap may be adjusted by sliding said holder within the limits of said slot.
 11. The invention according to claim 10 wherein said plunger contains a recess into which said horizontal portion of said holder is inserted. 